Hi, Martha. IMHO, I don't think the system can make effective use of expanded storage above, say 8GB or 9GB. What you want to have is enough expanded storage to satisfy the so-called 30 second paging requirement.
How do you tell if you have enough expanded storage to meet that goal? Why, with a good VM performance monitor, of course (but you already knew that. ). Happy Holidays. On 12/16/2010 12:50 PM, Martha McConaghy wrote: > I know that this question has come up numerous times in the past, but > I'm don't recall ever seeing a consensus on it. I know that z/VM needs > expanded storage. However, deciding how much is the trick. > > We will be moving to a z10 early in the new year. I'm trying to decide > how to divide the storage. If an LPAR is going to be running a lot of > Linux guests (some of them quite large), is it better to put as much storage > into main as possible with a small expanded....or cut back on the amount of > main and put it towards expanded? I've done the former in the past. However, > we now have a lot more Linux servers than ever before, some of which are > running pretty heavy apps, like Oracle. The current LPAR does do a lot of > paging to expanded and disk. While there will be more storage on the z10, it > isn't a lot amount more. > > So, for example, if I have 35G to use for 1 LPAR, would it be better to > define 30G main and 5G expanded or 25G main and 10G expanded? > > Martha > -- Dave Jones V/Soft Software www.vsoft-software.com Houston, TX 281.578.7544
